Video games such as action games and role-playing games make characters act in a three-dimensional virtual game space corresponding to operation input by users. Various three-dimensional objects are located in the three-dimensional virtual game space and they are generated by computer graphics.
The way for describing a fluid is devised. For example, the three-dimensional fluid is shown by generating the computer graphics with a three-dimensional simulation of the fluid in the three-dimensional virtual space shown in Non-patent literature 1 to 3.    Non-patent literature 1: Jonathan M. Cohen, Sarah Tariq, Simon Green, “Interactive Fluid-Particle Simulation using Translating Eulerian Grids”, Cohen interactive2010, (NVIDIA), [online] Jan. 4 2016, <http://jcohen.name/papers/Cohen_Interactive_2010.pdf>    Non-patent literature 2: Keenan Crane, Ignacio Llamas, Sarah Tariq, “Real-Time Simulation and Rendering of 3D Fluids”, Chapter 30, CPU Gem 3, (Hubert Nguyen), [online] Jan. 4, 2016, <http://www.cs.columbia.edu/˜keenan/Projects/GPUFluid/paper.pdf>    Non-patent literature 3: QING YANG, “Real-Time Simulation of 3 D Smoke on GPU”, Proceedings of the 3rd WSEAS Int. Conf. on CIRCUITS, SYSTEMS, SIGNAL and TELECOMMUNICATIONS (CISST'09), pp. 130-134, [online] Jan. 4, 2016, <http://www.wseas.us/e-library/conferences/2009/ningbo/CD-CISST/CISST25.pdf>